The cutting device covered by the present invention is particularly suitable for use in the tire manufacturing industry to which the following description refers, though purely by way of a non-limiting example which in no way limits the scope of the present invention.
In the tire manufacturing industry, certain tire parts are formed starting from continuous strips of elastomeric material. In more detail, transverse bevel cuts are made in the said strip by means of a blade inclined in relation to the surface supporting the uncut strip. By means of each of the said cuts, which are made in succession at a given position on said supporting surface, a strip portion, suitable for use in a tire, is cut off the end of the said continuous strip.
During each cutting operation, the blade, of whatever shape or type it may be, induces relatively severe cutting stress in the strip, on account of the inclined position of the blade in relation to the strip surface. At normal output rates, and with a strip the thickness of which exceeds a predetermined value, the said stress, which obviously depends on the type of blade, cutting speed and the type and thickness of material being cut, is usually severe enough to deform the strip by wrinkling the strip portion on the cutting line immediately ahead of the blade.
As such crumpling of the strip obviously results in inaccurate, undulated cuts, attempts have been made to reduce the said cutting stress by employing rotary blades. At the output rates permitted on current tire manufacturing machines, however, the sole employment of rotary blades has proven insufficient for preventing local deformation and wrinkling of relatively thick strips during cutting.